Saturday, October 4, 2008

Earth faces 'tsunami' of species loss

ANIMAL and plant species are vanishing at unprecedented rates, evidence that the Earth is facing a tsunami of mass extinction, warn experts gathering for a global conservation conference starting tomorrow.

Whether through habitat loss, pollution, hunting or indirectly by global warming, humans are to blame for what may be the first major die-off in 65 million years, they say.

More than 8000 ministers, UN officials, NGOs, scientists and business chiefs will be in Barcelona, Spain, for the World Conservation Congress, held every four years. The release on Monday of an update of the Red List, the global standard for conservation monitoring, will include the most comprehensive study made of the survival status of Earth's more than 5000 mammal species.

The biodiversity "bible" is the work of 1700 experts, and scientists who took part say it will make for grim reading. The 2007 edition already shows more than a third of 41,000 species surveyed face extinction: one in four mammals, one in eight birds, one in three amphibians, and 70% of plants.

Our closest evolutionary cousins, primates, are especially vulnerable. Hunted for food and traditional medicines, their habitat dwindling, more than 70% of known species in Asia, for example, are under threat.

"Biodiversity is disappearing at an accelerated rhythm and we have to act quickly to slow and prevent the extinction crisis," said Julia Marton-Lefevre, director general of the International Union for Conservation of Nature, organiser of the October 5-14 congress.

With 11,000 volunteer scientists and more than 1000 paid staff, the IUCN runs field projects around the globe. "No species is superfluous — each one is the product of millions of years of evolution and plays a role in the ecosystem," said Wendy Foden, head of the IUCN climate change and species program.

There are many reasons to protect the diversity of life on Earth, under pressure from loss of habitat, pollution, climate change and overexploitation, scientists say. One is the sheer scope of the change under way.

"The evidence is overwhelming — and we have really good data now — that what we are seeing is probably a mass extinction," the sixth in 450 million years, said Michael Hoffman, an IUCN mammal expert who worked on the Red List.

The pace of die-off is 100 to 1000 times higher than the so-called "background rate" of extinction — the average rate, over millions of years, at which species disappear. "Species extinctions across all these groups will have very far-reaching consequences on human beings," he said.

Mammals, for example, play critical roles in the regeneration of forests and savannahs by spreading plant seeds through their excrement. Forests, in turn, help blunt the impact of global warming. Coral reefs, dying due to pollution and acidification driven by warming seas, support thousands of species of fish on which hundreds of millions of humans depend for their food and livelihood.


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